Question 782000
Car II rate = x kph
D=135

Car I rate = x+20 kph
D=180

time  is same
t=d/r

180/(x+20)=135/x

cross multiply

180x=135(x+20)

180x=135x+135*20

45x=135*20

/45
x=135*20/45

x=60 kph Car II

Car I = 60 +20 = 80 kph